Faraaidh of wudhu

Fardh and sunnah acts of wudhu

Q:

1. What are fard acts of wudhu? If I want to wash my face and there is some sweat on my face, can I make my hand wet then wipe my face or washing my face is required?

2. Also, if I were to wash my arms or face, normally I wet my hand and touch the tap to close it and wipe my face after touching tap. The tap was wet due to me closing it, so is my wudu valid since my hand had mustamil (used water )?

3. Also when doing masah, if my hand touched my wet face and that water also came in doing masah is my wudu valid? (Here also mustamil water)

4. Is doing wudu in steps compulsory or not?

5. Is it compulsory to complete the wudu before the hands and face get dry?